This is the trailing shuck emerger stage of the Speckled Wing Quill. It imitates the insect accenting to the surface during the hatch with the nymphal shuck still attached to the emerging dun. The Speckled Winged Quills are often called "Callibaetis", which is the scientific name of the genus these mayflies belong too. They are found in slow moving water of streams and still water of lakes and ponds. Trout eat them in all stages of their life. A must for still water anglers.